I have a 69 with a LT1 swap.

It cranks but doesn't roll over.

I get 43 lbs at fuel rail , may go down to 40 after left for a few min . during cranking the gauge goes down a bit .. 30s.. Is this norm? I replaced the inline electronic fuel pump years ago.

I also hear the fuel pump relay switch during the fuel pump initiation at key turn, then during crank I can hear/feel it switch back? Is this norm?

I do get spark with a spark plug test, I also get power at the injectors...

If I do get it to roll over its briefly after I left
the fuel pump prime a few times or with carb cleaner in the intake

I'm thinking fuel pump or relay arm... Any suggestions are welcomed , please , ha.

 

Could it be my vats? Maybe it just so happened to go out ?

 

did you test the injectors with a noid light to see if they were being told to fire?

 

did you see this https://camaroforums.com/forum/lt1-l...t-start-65637/

also here are a couple places to learn
4th Gen LT1 F-Body Tech Aids

https://camaroforums.com/forum/93-02...rt-here-38462/